Martensite stainless steel

ABSTRACT

THE PROPOSED INVENTION RELATES TO A MATERIAL FOR WELDING-WIRE FOR STEELS, WHICH MATERIAL COMPRISES CARBON, MANGANESE, SILICON, NICKEL, CHROMIUM, TITANIUM, ALUMINUM, MOLYBDENUM, ZIRCONIUM, CALCIUM, BORON AND IRON.

United States Patent O 3,690,869 MARTENSITE STAINLESS STEEL YakovMikhailovich Potak, zelenodolskaya, ulitsa 23, korpus 1, kv. 29; JulianFelixovich Orzhekhovsky, Leningradskoe shosse 75, korpus 2, kv. 25;Vladimir Vladimirovich Sachkov, Scherbakovskaya ulitsa 40, kv. 160; EfimSolomonovich Kagan, Profsojnznaya ulitsa 40, korpus 1, kv. Anna IvanovnaValdman, l-i pereulok Izmailovskogo zverints'a 7, kv. 2; NadezhdaNikolaevna Shpagina, 9-ya ulitsa Sokolinoi Gory 3, kv. 40; MikhailVasilievich Poplavko-Mikhailov, Maly Pionersky pereulok 5, kv. 56;Alexandr Pavlovich Fomin, 4-i Voikovsky proezd 3, korpus 1, kv. 154;.and Simon Leibovich Natapov, Leningradsky prospekt 24, kv. 8, all ofMoscow, USSR. No Drawing. Filed Aug. 26, 1970, Ser. No. 67,217

Int. Cl. C22c 37/10 US. Cl. 75-124 1 Claim ABSTRACT OF THE DISCLOSUREThe proposed invention relates to a material for welding-wire forsteels, which material comprises carbon, manganese, silicon, nickel,chromium, titanium, aluminum, molybdenum, zirconium, calcium, boron andiron.

FIELD OF THE INVENTION The present invention relates to a material forweldingwires for welding steel, mainly stainless steel.

DESCRIPTION OF PRIOR ART Employed presently for welding high-strengthstainless steels with a tensile strength of 120-140 kg./mm. are fillerwires, in which the carbon content is usually 0.07- 0.12%.

Also known in the art is welding wire, comprising (in weight percent): I

C-not more than 0.08%, Si-not more than 0.7%. Mnnot more than 1%,Ni4.5-5.8%, Cr13.5-14.8%, Ti-0.03-0. Cu1.75-2.5%,

Snot more than 0.025% P-not more than 0.03% Fethe rest.

*Undesirable inevitable admixtures present in filling stock.

FIELD OF THE INVENTION The object of our invention is to provide awelding wire, that ensures high impact ductility of weld metal withoutits heat treatment after the welding process, at the same timemaintaining high strength of the welded joints.

3,690,869 Patented Sept. 12, 1972 DESCRIPTION OF THE INVENTION Proposedherein is an alloy composition for welding wire for steel, mainlystainless steel comprising carbon, silicon, manganese, nickel, chromium,titanium, iron. The distinguishing feature of the wire is thatintroduced thereinto are aluminum, molybdenum, zirconium, calcium,boron, with the following ratio of all the constituents (in weightpercent):

C-not more than 0.03 Mn0.6-0.9 Si-1.4-1.7% Ni-8.5-9.0% Cr11.4-11.8%,Ti0.2-0.3 Al--0.0S-0.1% Mo-l.8-2.2% Zr0.02-0.08 Ca--0.00 l-0.05B0.001-0.003 Fe-the rest.

Employment of the proposed wire without any subsequent heat treatment ofthe welded joints makes it possible to obtain a weld metal with amartensite structure featuring high ductility (l4 kgm./cm. due to aparticularly low carbon content (below 0.03%

Introduction of zirconium and titanium into the wire composition permitsa fine-grained structure of the weld, which also raises the ductility ofthe deposited metal.

A formation in the weld structure of fine inclusions of 6-ferriteexcludes columnar crystallization of the weld metal which would lead tothe reduction of its ductility.

Unlike the aforesaid prior art composition for weldingwire, whereinmetal is deoxidized in the course of welding mainly on the account ofthe considerably high carbon content (not in excess of 0.08%), in theproposed wire comprising 0.03% of carbon and less, deoxidation isachieved on' the account of elevated content of silicon and manganese,and presence of titanium and aluminum.

DESCRIPTION OF PREFERRED EMBODIMENTS For better understanding thesubject matter of the invention, given below are examples of preferredcompositions of the proposed welding wire, and a descriptionof theirproperties.

1 EXAMPLE '1 The wire may have the following composition .(in weightpercent) *llgndeslrabl-e inevitable admixtures present in the fillingstoc ness of the welded components being 10-30 mm. are given in thefollowing table.

Numeric values of mechanical Ser. No. Mechanical characteristics Unitcharacteristics 1 Tensile strength of the welded joint KgJmJnJ 110 2Yield point of the welded joint Kg./mm. 3 Impact ductility of weld metalwith a Menage KgmJcm. 12

notch (radius in the notch equaling 1 mm.) at room temperature. 4 Impactductility of weld metal with a Menage Kgm./em I notch (radius in thenotch equaling 1 mm.) at a temperature of -70 C. 5 Impact ductility ofweld metal with a Menage KgmJcm i 7 notch (radius in the notch equaling1 mm.) at a temperature of --196 C. 6 Impact ductility of weld metal,specimen with Kgm/cm I 8 a fatigue crack 1.5 mm. deep, at roomtemperature.

EXAMPLE 2 In welding low-carbon steels with the proposed wire no Thealloy may have the following composition (in weight percent) Cnot inexcess of 0.03% Mn0.8%

Cr--l1.6%

Caz-0.003%

S-not in excess of 0.001% P--not in excess of 0.001%

Undesirable inevitable admixtures present in the filling stock.

EXAMPLE 3 The alloy may have the following composition (in weightpercent) heat treatment is necessary after welding, which makesproducing large-size welded structures possible. Welded joints with theproposed wire, unlike all the conventional martensite fillers, arecapable of maintaining high ductility not only at low temperatures C.),but at cryogen temperatures (196 C.) as well. Therefore employment ofsuch wire permits providing strong welded units for various machines ofcryogen technology.

The proposed welding wire of the above-described composition must beproduced in vacuum induction furnaces.

What we claim is:

1. A martensite stainless steel for use as a filler in welding steels,mainly stainless steels, consisting of:

7/1936 Lohr -124 4/1965 Fujimura 75128 T 1/ 1968 Ziotkowski 751243,408,178 10/1968 Myers 75-124 3,556,776 1/1971 Clarke 75124 HYLANDBIZOT, Primary Examiner US. Cl. X.R.

